Symbolizationis forcing groups to wear symbols to identify them as different
On September 1, 1941, Reinhard Heydrich decreed that all Jews in the German empire six years of age or older were to wear a badge which consisted of a yellow Star on a black field to be worn on the chest, with the word "Jew" inscribed inside the star in German or in the local language. This applied to all German Jews and Jews in Germany's conquered territories. There were heavy penalties for those caught not wearing it.
Source: United States Holocaust Memorial Museum. "Jewish Badge During the Nazi Era." Holocaust Encyclopedia. https://encyclopedia.ushmm.org/content/en/article/jewish-badge-during-the-nazi-era.